Hydrangea plant named ‘H216901’

ABSTRACT

A new and distinct cultivar of  Hydrangea  plant named ‘H216901’, characterized by its upright and mounding plant habit; vigorous growth habit; rapid growth rate; freely branching habit; strong and sturdy stems; freely and uniformly flowering habit; mophead-type inflorescences with numerous dark red purple-colored sterile flowers; and good postproduction longevity.

Botanical designation: Hydrangea macrophylla.

Cultivar denomination: ‘H216901’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Hydrangea plant, botanically known as Hydrangea macrophylla, commercially referred to as a mophead-type Hydrangea and hereinafter referred to by the name ‘H216901’.

The new Hydrangea plant is a product of a planned breeding program conducted by the Inventor in De Kwakel, The Netherlands. The objective of the breeding program was to create new freely-branching Hydrangea plants with strong sturdy stems, large inflorescences, attractive flower color and good postproduction longevity.

The new Hydrangea plant is a naturally-occurring whole plant mutation of Hydrangea macrophylla ‘Agrihydradrie’, disclosed in U.S. Plant Pat. No. 19,726. The new Hydrangea plant was discovered and selected by the Inventor as a single flowering plant from within a population of plants of ‘Agrihydradrie’ in a controlled greenhouse environment in De Kwakel, The Netherlands in May, 2012.

Asexual reproduction of the new Hydrangea plant by vegetative terminal cuttings in a controlled environment in De Kwakel, The Netherlands since September, 2012 has shown that the unique features of this new Hydrangea plant are stable and reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

Plants of the new Hydrangea have not been observed under all possible combinations of environmental conditions and cultural practices. The phenotype may vary somewhat with variations in environmental conditions such as temperature and light intensity without, however, any variance in genotype.

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘H216901’. These characteristics in combination distinguish ‘H216901’ as a new and distinct Hydrangea plant:

-   -   1. Upright and mounding plant habit; vigorous growth habit.     -   2. Rapid growth rate; freely branching habit.     -   3. Strong and sturdy stems.     -   4. Freely and uniformly flowering habit.     -   5. Mophead-type inflorescences with numerous dark red         purple-colored sterile flowers.     -   6. Good postproduction longevity.

Plants of the new Hydrangea can be compared to plants of the parent, ‘Agrihydradrie’. Plants of the new Hydrangea differ primarily from plants of ‘Agrihydradrie’ in sterile flower sepal color as plants of the new Hydrangea have darker red purple-colored sterile flower sepals than plants of ‘Agrihydradrie’. In addition, plants of the new Hydrangea have darker green-colored leaves than plants of ‘Agrihydradrie’.

Plants of the new Hydrangea can be compared to plants of the Hydrangea macrophylla ‘Leuchtfeuer’, not patented. In side-by-side comparisons conducted in De Kwakel, The Netherlands, plants of the new Hydrangea differ from plants of ‘Leuchtfeuer’ in the following characteristics:

-   -   1. Plants of the new Hydrangea are more compact than and not as         vigorous as plants of ‘Leuchtfeuer’.     -   2. Plants of the new Hydrangea and ‘Leuchtfeuer’ differ in         sterile flower sepal color as plants of ‘Leuchtfeuer’ have dark         pink to deep purple-colored sterile flower sepals.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying colored photographs illustrate the unique appearance of the new Hydrangea plant showing the colors as true as it is reasonably possible to obtain in colored reproductions of this type. Colors in the photographs may differ from the color values cited in the detailed botanical description which accurately describe the colors of the new Hydrangea plant.

The photograph on the first sheet is a top perspective view of a typical flowering plant of ‘H216901’ (upper part of the sheet) and ‘Agrihydradrie’ (lower part of the sheet).

The photograph on the second sheet is a close-up view of a typical inflorescence of ‘H216901’.

DETAILED BOTANICAL DESCRIPTION

Plants used in the aforementioned photographs and in the following description were grown during the late spring and early summer in 15-cm containers in a glass-covered greenhouse in De Kwakel, The Netherlands and under cultural practices typical of commercial Hydrangea production. During the production of the plants, day and night temperatures averaged 17° C. Plants of the new Hydrangea were pinched one time and were one year old when the photographs and description were taken. In the following description, color references are made to The Royal Horticultural Society Colour Chart, 1995 Edition, except where general terms of ordinary dictionary significance are used.

-   Botanical description: Hydrangea macrophylla ‘H216901’. -   Parentage: Naturally-occurring whole plant mutation of Hydrangea     macrophylla ‘Agrihydradrie’, disclosed in U.S. Plant Pat. No.     19,726. -   Propagation:     -   -   Type cutting.—By vegetative cuttings.         -   Time to initiate roots, summer.—About two weeks at             temperatures about 23° C.         -   Time to initiate roots, winter.—About 18 days at             temperatures about 18° C.         -   Time to produce a rooted young plant, summer.—About four             weeks at temperatures about 23° C.         -   Time to produce a rooted young plant, winter.—About five             weeks at temperatures about 18° C.         -   Root description.—Thick; typically whitish brown in color,             actual color of the roots is dependent on substrate             composition, water quality, fertilizer type and formulation,             substrate temperature and physiological age of roots.         -   Rooting habit.—Freely branching; dense. -   Plant description:     -   -   Plant and growth habit.—Upright and mounding plant habit;             strong and sturdy stems; rapid growth rate and vigorous             growth habit.         -   Plant height.—About 30 cm to 40 cm.         -   Plant diameter or area of spread.—About 40 cm. -   Lateral branch description:     -   -   Branching habit.—Freely branching habit; when pinched, about             six lateral branches develop per plant.         -   Length.—About 25 cm.         -   Diameter.—About 6 mm.         -   Internode length.—About 6 cm.         -   Texture.—Smooth, glabrous; fully developed, woody.         -   Aspect.—Upright to about 20° from vertical.         -   Strength.—Strong, sturdy.         -   Color.—Close to 146C; at internodes, close to 187A;             lenticels, close to 187A; when woody, close to 177C. -   Leaf description:     -   -   Arrangement.—Opposite, simple.         -   Length.—About 10 cm.         -   Width.—About 7 cm to 8 cm.         -   Shape.—Ovate.         -   Apex.—Acute to acuminate.         -   Base.—Obtuse.         -   Margin.—Dentate to serrate.         -   Texture, upper and lower surfaces.—Rugose, glabrous.         -   Venation pattern.—Pinnate.         -   Color.—Developing and fully developed leaves, upper surface:             Close to 139A; venation, close to 146B. Developing and fully             developed leaves, lower surface: Close to 139B; venation,             close to 146B.         -   Petioles.—Length: About 1.5 cm. Diameter: About 3 mm.             Texture, upper and lower surfaces: Smooth, glabrous. Color,             upper and lower surfaces: Close to 146B. -   Flower description:     -   -   Flower type and habit.—Showy sterile flowers and small,             inconspicuous star-shaped fertile flowers arranged on             mophead-type terminal panicles; panicles globular in shape;             flowers face upright to outwardly.         -   Fragrance.—None detected.         -   Natural flowering season.—Plants begin flowering about one             year after planting; continuous flowering during the summer             in Northern Europe.         -   Flower longevity.—Sterile flowers last about four months on             the plant, sterile flowers persistent; fertile flowers last             about one month on the plant, fertile flowers not             persistent.         -   Quantity of flowers.—Freely flowering habit; about 40             sterile flowers per panicle and about 15 to 20 fertile             flowers per panicle.         -   Panicle height.—About 6 cm.         -   Panicle diameter.—About 11 cm.         -   Sterile flower buds.—Length: About 3 mm. Diameter: About             3 mm. Shape: Flattened globular. Color: Close to 144A.         -   Fertile flower buds.—Length: About 3 mm. Diameter: About             3 mm. Shape: Flattened globular. Color: Close to 144A.         -   Sterile flower diameter.—About 3.5 cm.         -   Sterile flower depth (height).—About 1 cm.         -   Fertile flower diameter.—About 6 mm.         -   Fertile flower depth (height).—About 6 mm.         -   Petals, sterile flowers.—Quantity and arrangement: If             present, about four to five in a single whorl. Length: About             3.5 mm. Width: About 2 mm. Shape: Ovate. Apex: Acute. Base:             Attenuate. Margin: Entire. Texture, upper and lower             surfaces: Smooth, glabrous. Color: When opening, upper and             lower surfaces: Close to 57D. Fully opened, upper and lower             surfaces: Close to 57C; color does not change with             development.         -   Petals, fertile flowers.—Quantity and arrangement: About             four to five in a single whorl. Length: About 3.5 mm. Width:             About 2 mm. Shape: Ovate. Apex: Acute. Base: Attenuate.             Margin: Entire. Texture, upper and lower surfaces: Smooth,             glabrous. Color: When opening, upper and lower surfaces:             Close to 149D. Fully opened, upper and lower surfaces: Close             to 57C; color does not change with development.         -   Sepals, sterile flowers.—Quantity and arrangement: Four in a             single whorl. Length: About 2 cm. Width: About 2 cm. Shape:             Deltoid. Apex: Acute or retuse. Base: Cuneate. Margin:             Entire. Texture, upper and lower surfaces: Smooth, glabrous.             Color: When opening, upper and lower surfaces: Close to             144B. Fully opened, upper surface: Close to 63A; color             becoming closer to 59A with development. Fully opened, lower             surface: Close to 63B; color becoming closer to 59C with             development.         -   Sepals, fertile flowers.—Quantity and arrangement: Five in a             single whorl. Length: About 2 mm. Width: About 2 mm. Shape:             Ovate. Apex: Acute. Base: Obtuse. Margin: Entire. Texture,             upper and lower surfaces: Smooth, glabrous. Color: When             opening, upper and lower surfaces: Close to 62D. Fully             opened, upper and lower surfaces: Close to 62D; color does             not change with development.         -   Pedicels, sterile flowers.—Length: About 2 cm. Diameter:             About 1.5 mm. Strength: Strong. Aspect: About 45° from             vertical. Texture: Smooth, glabrous. Color: Close to 59A.         -   Pedicels, fertile flowers.—Length: About 4 mm. Diameter:             About 1 mm. Strength: Strong. Aspect: Mostly upright.             Texture: Smooth, glabrous. Color: Close to 63A.         -   Reproductive organs, sterile flowers.—Stamens: Quantity per             flower: Eight. Filament length: About 2 mm. Filament color:             Close to 57D. Anther shape: Conical. Anther length: About             1 mm. Anther color: Close to 66D. Pollen amount: Scarce.             Pollen color: Close to 155D. Pistils: None observed on             sterile flowers.         -   Reproductive organs, fertile flowers.—Stamens: Quantity per             flower: Eight. Filament length: About 1 mm. Filament color:             Close to 155D. Anther shape: Conical. Anther length: About             1 mm. Anther color: Close to 145D. Pollen amount: Abundant.             Pollen color: Close to 155D. Pistils: Pistil quantity per             flower: Three. Pistil length: About 1 mm. Stigma shape:             Oval. Stigma color: Close to 155C. Style length: About 1 mm.             Style color: Close to 150D. Ovary color: Close to 150D         -   Seeds.—Only produced on fertile flowers. Quantity per             flower: About 20 to 30. Length: About 0.5 mm. Diameter:             About 0.1 mm. Color: Close to 200C. -   Disease & pest resistance: Under commercial production conditions,     plants of the new Hydrangea have not been observed to be resistant     to pathogens and pests common to Hydrangea plants. -   Temperature tolerance: Plants of the new Hydrangea have been shown     to be tolerant to temperatures ranging from about 3° C. to about 38°     C. 

It is claimed:
 1. A new and distinct Hydrangea plant named ‘H216901’ as illustrated and described. 